1. Field of the Invention
The present invention relates to foams derived from hydrocarbon liquids which contain fluoropolymer foaming agents and their use in fracturing subterranean formations.
2. Prior Art
"Fluorocarbon Surfactants: Their Current and Future Applications in Oil and Gas Well Stimulation," by David L. Holcomb, presented at the 18th Annual Southwestern Petroleum Short Course, Lubbock Texas, April, 1971, and "Fluorocarbon Surfactants: Their Current and Future Applications in Oil and Gas Well Stimulation," by David L. Holcomb, presented at the 24th Annual Southwestern Petroleum Short Course, Lubbock, Texas, April, 1977, both disclose the use of fluorocarbon surfactants in oil and gas well stimulation.
U.S. Pat. Nos. 3,282,905 and 3,491,169 both disclose copolymers of alkyl acrylates or alkyl methacrylates with fluoroalkyl acrylates or fluoroalkyl methacrylates.
U.S. Pat. No. 3,937,283 discloses foam fracturing subterranean formations.
U.S. Pat. No. 4,148,217 discloses a method for obtaining a measure of foam quality so that surfactants can be evaluated for a steam-diversion oil recovery process.